The present invention relates to a data transmission method between a computer and a printer in a computer network system.
In a conventional computer network system, when a data file on a particular application is outputted to a printer connected to a computer network in response to the user""s manipulation of a client computer, data are sent/received in the following manner. In the first place, the application is started up on the client computer to open a subject data file to be printed out. Then, a pre-installed printer driver for the printer is retrieved from the client computer at a print command issued by the application. Then, the subject data file is converted to a command exclusively used for the printer by the printer driver. Finally, the converted data file is sent to the printer and printed out.
In case of a bitmap method mostly adopted by inexpensive printers, the data file opened by the application may be converted to adequate bitmap data on the client computer in response to the resolution of the printer before it is sent to the printer.
On the other hand, in case that the data are sent in the page-description language represented by PostScript, a function for converting the subject data file to the page-description language is provided to the computer, so that the printer interprets and converts the page-description language to the bitmap data and prints out the same.
However, according to the above data sending methods, the client computer has to run a series of jobs, such as starting up the application, opening the subject data file, issuing a print command, and converting the data by means of the printer driver. Thus, the CPU (Central Processing Unit) of the client computer is almost fully occupied while these jobs are run, thereby affecting the other jobs also run by the client computer. In addition, in case of an application of a large size, the client computer takes a while to finish these jobs, thereby reducing the user""s workability.
Also, in case of the bitmap data sending method adopted by inexpensive printers, a large volume of data are transmitted. Thus, a traffic volume in the computer network is increased, and the sending/receiving of the other data throughout the computer network is affected.
In case of the data sending method in the page-description language, the page-description language must be pre-installed in the client computer, while a function for interpreting the page-description language must be provided to the printer. Thus, the printer also demands a high-speed CPU, a memory and a hard disk, and consequently, becomes very expensive. Further, in case that complicated data are printed out, quite a heavy burden is applied on the client computer and the CPU in the printer while the data are converted to the page-description language. Thus, there may be some cases where the printing speed drops below the rated printing speed.
Moreover, each type of printer demands their respective printer drivers in accordance with their specifications. Thus, the user has to install a specific print driver for the user""s printer into the client computer. In case that various types of printers are connected to the network and shared in the network system, the user has to manipulate the client computer in different manners depending on which printer the user is going to use, and this manipulation is quite a burden on the user. Also, the user has to manage the version of each printer driver, which adds up a burden on the user.
Furthermore, since the printer driver is developed for each type of printer in accordance with their respective specifications, the development demands considerable time and money.
It is therefore an object of the present invention to provide a printer enclosing a network computer and employed on a computer network, which can reduce a burden on a client computer that issues a print command and a traffic volume in the computer network during a printing job.
To fulfill the above and other objects, a printer of the present invention, enclosing a network computer and employed on a computer network, is characterized in that the network computer is furnished with:
a network control section for downloading a subject data file to be printed out and an application corresponding to the subject data file from the computer network; and
an image converting section for starting up the application and converting the subject data file into a raster image.
According to the above arrangement, the subject data file and application corresponding to the subject data file are sent to the printer enclosing the network computer as the data for the printing job. Generally, a volume of the subject data file and application is smaller than a volume of the conventional bitmap data. Thus, according to the above arrangement, a traffic volume in the computer network can be reduced.
The job of converting the subject data file to a raster image using the application corresponding to the subject data file is carried out by the image converting section included in the printer enclosing the network computer on the application downloaded by the network control section. In other words, it is no longer necessary to provide a printer driver to the client computer or the like that issues a print command to enable the same to carry out the above converting job.
Thus, not only the costs can be reduced by saving the time and money for developing the printer driver, but also a burden on the user, such as management of the version of each printer driver, can be reduced. In addition, since a capacity of a hard disk or a memory necessary to store the printer driver and the like can be reduced, the client computer can be downsized and less expensive. Further, there is an advantage that, when the user enters a print command, the user no longer has to select an adequate printer driver for the printer the user is going to use.
In a conventionally known printing system, the client computer is furnished with a function for converting the data file to the page-description language and the printer is furnished with a function for interpreting the page-description language. In this conventional system, the printer has to maintain and manage the application necessary for interpreting the page-description language.
In contrast, the present invention is arranged in such a manner that the network control section downloads an application necessary for converting the subject data file to a raster image from the computer network. Thus, according to the arrangement of the present invention, the printer enclosing the network computer has to neither maintain nor manage the above application.
Further, since it is the image converting section provided in the printer enclosing the network computer that carries out the above converting job, the client computer only has to issue a print command to the printer enclosing the network computer. Thus, the client computer can carry out other jobs once it has issued the print command, thereby improving its operation efficiency.
Also, a computer network system of the present invention is a computer network system, wherein a printer enclosing a network computer is connected to a plurality of apparatuses including a computer, and characterized in that the network computer enclosed in the printer is furnished with:
a network control section for downloading a subject data file to be printed out and an application corresponding to the subject data file from any of said plurality of apparatuses on the computer network system; and
an image converting section for starting up the application and converting the subject data file into a raster image.
According to the above arrangement, the subject data file to be printed out and the application necessary for converting the subject data file to a raster image are sent to the printer enclosing the network computer as the data for the printing job. Generally, the subject data file and application are smaller in size compared with the conventional bitmap data. Consequently, it has become possible to provide a computer network system, in which an increase in a traffic volume during the printing job can be suppressed.
Also, it is the image converting section provided in the printer that carries out the job of converting the subject data file to a raster image on the application downloaded by the network control section. In other words, it is no longer necessary to provide a printer driver or the like to the client computer or the like that issues a print command. Thus, not only the costs can be reduced by saving the time and money for developing the printer driver, but also a burden on the user, such as management of the version of each printer driver, can be reduced. In addition, the client computer can be downsized and less expensive by reducing capacities of the hard disk and memory for storing the printer driver and the like. Consequently, it has become possible to provide an inexpensive computer network system. Further, when the user enters a print command, the user no longer has to select an adequate printer driver for the printer the user is going to use for the printing job. Thus, there can be attained an advantage that a computer network system with excellent operability can be provided.
Also, compared with a conventional system, in which the client computer is furnished with a function for converting the data file into the page-description language and the printer is furnished with a function for interpreting the page-description language, the above arrangement allows the network control section to download an application necessary for converting the subject data file to be printed out to a raster image from any of the apparatuses (such as the client computer and application server) on the computer network system. Thus, the printer has to neither maintain nor manage the application necessary for converting the subject data file to a raster image.
Further, since the converting job is carried out in the printer, the client computer or the like that issues a print command to the printer can carry out other jobs once it has issued the print command. Consequently, not only a burden on the client computer can be reduced, but also the operation efficiency of the client computer, and hence an overall operation efficiency of the computer network system can be improved.
Also, a printing method of the present invention is a printing method carried out by a printer connected to a computer network, and characterized by being composed of the steps of:
downloading a subject data file to be printed out and an application corresponding to the subject data file from the computer network; and
staring up the application downloaded and converting the subject data file to a raster image.
According to the above method, the subject data file and an application necessary for converting the subject data file to a raster image are sent to the printer as the data for the printing job. The subject data file and application are smaller in size compared with the conventional bitmap data. Consequently, an increase in a traffic volume in the computer network during the printing job can be suppressed.
Also, it is the printer connected to the computer network that carries out the job of converting the subject data file to a raster image. In other words, it is no longer necessary to provide a printer driver or the like to the client computer or the like that issues a print command. Thus, not only the costs can be reduced by saving the time and money for developing the printer driver, but also a burden on the user, such as management of the version of each printer driver, can be reduced.
In addition, since the printer driver can be omitted, the client computer can be downsized and less expensive by reducing capacities of the hard disk and memory for storing the printer driver and the like. Further, when the user enters a print command, the user no longer has to select an adequate printer driver for the printer the user is going to use for the printing job, thereby reducing a burden on the user when the user manipulates the client computer.
In a conventionally known printing method, the client computer converts the data file into the page-description language and the printer interprets the page-description language and carries out the printing job. Thus, in the above conventional printing method, both the client computer and printer have to maintain and manage the page-description language. In contrast, in the above method, the network computer downloads an application necessary for converting the subject data file to be printed out to a raster image from any of the apparatuses (such as the client computer and application server) on the computer network system. Thus, the printer has to neither maintain nor manage the application necessary for converting the subject data file to a raster image.
Further, since the above converting job is carried out in the printer, the client computer or the like that issues a print command to the printer can carry out other jobs once it has issued the print command. Consequently, not only a burden on the client computer can be reduced, but also its operation efficiency can be improved.
Furthermore, a program to direct a computer to carry out the above printing method of the present invention can be recorded into a computer-readable recording medium.
For a fuller understanding of the nature and advantages of the invention, reference should be made to the ensuing detailed description taken in conjunction with the accompanying drawings.